Vacuum drying-oven



J. D. TAYLOR.

VACUUM DRYING OVEN. APPLICATION FILED MAR. 21. 1920.

1,365,207. Patented Jan. 11,1921;

3 SHEETS-SHEET I.

781% Zarnje .73 1'07 2 AMQW .l. D. TAYLOR.

VACUUM DRYING OVEN.

APPLICATION FILED MAR. 31. I920- 3 SHEETS-SHEET 2.

Patented Jan. 11, 1921.

J. D. TAYLOR.

VACUUM DRYING OVEN. APPLICATION FILED MAR. 3I. I920.

1,365,207, Patented Jan. 11, 1921.

3 SHEETS-SHEET 3- for UNITED STATES PATENT OFFICE.

JOHN DARNLEY TAYLOR, OF KINGSTON HILL, ENGLAND.

VACUUM DRYING-OVEN.

Application filed March 31.

To all whom it may concern:

Be it known that I, JoHN DARNLEY TAY- non, of l'lighwood House, KingstonHill, county of Surrey, England, a subject of the King of Great Britain,have invented new and useful ImprovementsRelating to VacuumDrying-Ovens, of which the following is a specification.

This invention relates to heating shelves or chests for drying stoves orovens and particularly to shelves for use in vacuum drying stoves orovens of the rectangular type. Shelves or chests of this character arearranged in superposed relationship in the stove or oven at suitabledistances apart to receive the containers for the wet material to bedried and they are usually constructed of two rolled steel plates whichare riveted together at their edges through an 1ntermediate distancering so as to form the desired internal space for the steam or otherdrying medium and in some cases it has been suggested to build them upof tubular members.

In order to obtain the necessary rigidity it is also customary to staythe plates all. over with countersunk studs or stays. WVhile thisconstruction of shelf has been generally adopted it presents a number ofdefects which considerably affect its utility. For example a shelf ofthis character is expensive to make and the construction is such as todisturb perfect circulation of the heating medium so that air or waterlogging often occurs which as is well known prevents the material undertreatment being uniformly heated. Again no apprecia- I ble heat isimparted to the sides of the shelf so that heavy condensation takesplace on the walls of the stove. This condensation necessarily prolongsthe drying operation and considerably increases the "consumption ofpower. Moreover the shelves are extremely heavy to handle and owing totheir bulky construction much oven space that could be usefully employedwith a compacter shelf is wasted.

The object of the present invention is to overcome the aforesaid defectsand provide a compact shelf or chest which will enable the drying stoveor oven to be worked far more efiiciently than has heretofore beenpossible.

According to thisinvention the shelf oomprises a structure built upentirely of tubular members and presenting an extensive Specification ofLetters Patent. Patent d J 11 1921 1920. Serial No. 370,230.

and practically continuous contact heating surface. It consists of aseries of flattened tubular members mounted or arranged in spacedrelationship between tubular supporting members and having their majorcross sectional axes parallel with the surface of the shelf. The tubularsupporting members or side tubes are preferably of circular crosssection but they may be made of flattened formation and in this casetheir major cross sectional axes would be substantially normal tothemajor axes of the flattenedcross tubes supported thereby.

In order that the said invention may be clearly understood and'readilycarried into effect the same will now be described more fully withreference to the accompanying drawings in which Figure 1 is a partialsectional plan of a drying stove or oven containing one form of theimproved shelf.

Fig. 2 is a partial plan of the stove and shelf on an enlarged scale.

Fig. 3 is a section through a superposed series of the improved shelvesthe left hand side of this figure illustrating the inlet and the righthand side of the figure the exhaust or outlet side of the shelves.

Fig. 4 is a front elevation of a vacuum drying stove or oven fitted witha modified form of the improved shelf with part of the.

door cut away to expose the shelves.

Fig. 5 is an enlarged sectional view of the shelves and the ledges forsupporting the same in the stove.

Fig. 6 represents a fragmentary plan view of a modified'form of shelfembodying this invention.

Referring to Figs. 1 to 3 the stove is of conventional form andcomprises a main casing 1 which is provided with a hinged door 2 adaptedto be securely retained in the closed position by means of swing bolts 3which engage bifurcated lugs 3 formed on the edges of the door. 'Eachbolt is'pi'ovided with a hand nut 4: which is screwed on to thecorresponding lugto force the door against a suitable seating formed onthe mouth of the casing 1. Each side of the casing is provided with asuperposed series of ledges 6 which are adapted to receive and supportthe shelves-designated as *a whole by the numeral 7as they are slid intothe stove through the open mouth thereof. The shelves 7 are built upentirely of tubular members and in the arrangement shown in Figs. 1 to 3each shelf comprises a series of flattened cross tubes 8 which extend inspaced relationship between two side tubes 9. The ends of the fiattenedtubes 8 fit into holes or apertures formed in the side tubes 9 and theymay be welded or expanded therein to make a tight and secure connection.If desired the ends of the tubes 8 may be made of circular section andcorresponding holes or apertures formed in the side tubes to receive thesame. The heating medium such as steam is sup plied to the shelves bymeans of expansion bends 10 which are connected to the front ends of theright hand tube 9 Fig. 1 and to a vertical supply pipe 11 located in apocket .12 formed in the side wall of the casing l of the stove and saidheating medium after passing through the shelves is conducted to anexhaust pipe 1 through similar expansion bends 15 connected to the lefthand side tubes 9 of the shelves.

It will be seen from Fig. 3 that the inlet bends 10 are connected tospigots 16 formed on caps 17 which close the ends of the side tubes 9.These spigots 16 are arranged eccentrically on said caps so that whenthe latter are in position said spigots 16 will be dis posed well abovethe central longitudinal axes of the side tubes. Similar caps 17 areused to close the exhaust ends of the opposite side tubes 9 but they areso arranged thereon that the spigots 16 are disposed below the centralaxes of the side tubes 9 said spigots being connected to a drain pipe 18having a suitable draw off cook 19 thereon. In this manner all water inthe tubes may be drained off and the arrangement of the connections issuch as to effectively prevent logging.

In the form of shelf shown in Figs. 4t and 5 the side tubes 9 instead ofbeing circular are made of flattened section and are provided withsuitably spaced openings or aper tures to receive the flattened or ovalends of the cross tubes 8. The cross tubes may be welded to the sidetubes 9 as in the construction previously described. The necessary inletand outlet connections for the heating medium may also be of the same orof other suitable type and to facilitate the making thereof the ends ofthe flattened sides tubes 9 are made of circular section to receive theaforementioned spigoted end caps.

In Fig. 6 I have illustrated a modified form of shelf which from thepoint of View of simplicity of manufacture possesses manifestadvantages. In this construction the cross tubes are of flattened crosssection as in the previously described arrangements but the end portions20 are rectangular in cross section. In assembling the shelf the tubes 8are arranged side by side and welded together at the points of contact21 to form a unitary structure. The side tubes 9 are slottedlongitudinally to receive the rectangular ends of the assembled crosstubes 8 which are then welded in position to form a fluid tightconnection with said side tubes 9.

It will be seen that in each case the shelf is of compact and lightconstruction and such as to permit of considerable heat being impartedto the ends of the shelf and the side walls of the stove. shelf? isinexpensive to manufacture and owing to its small depth as compared withthe usual form of shelf enables more of the internal space of the stoveor oven to be utilized for drying purposes. It affords extensive contactheating surface and moreover insures perfect circulation of the heatingmedium with freedom from water or air logging as no water can lodge inthe cross tubes of the shelf and no logging can take place in the sidetubes as the outlet end is disposed at a slightly lower level than theinlet end.

It will be understood that the shelf may be constructed of tubes ofsteel, copper, brass, or other suitable metal and that suitable heatingmedium may be used therein.

Having described my invention, what I claim and desire to secure byetters Patent is 1. A heating shelf or chest for drying stoves or ovenscomprising a series of flattened tubular members mounted or arranged inspaced relationship between tubular supporting members and having theirmajor cross sectional axes extending parallel with the surface of theshelf.

2. A heating shelf or chest for drying stoves or ovens comprising aseries of fiattened tubular members mounted or arranged in spacedrelationship between flattened tubular supporting members and havingtheir major cross sectional axes substantially normal to the major axesof the tubular supporting members.

3. A heating shelf or chest for drying stoves or ovens comprising aseries of fiattened tubular members having suitably formed ends whichare adapted to be welded or expanded in spaced openings or aperturesformed in two tubular supporting members extending transversely to saidfiattened tubular members.

4. A heating shelf or chest for drying stoves or ovens comprising aseries of flattened tubular members mounted or arranged in spacedrelationship between tubular supporting members, and eccentricallydisposed inlet and outlet spigot connections between said tubularmembers.

JOHN DARNLEY TAYLOR.

The improved

